The Proceedings of the Eighth International Conference on Creationism (2018)

D. Planar and massive beds The most common bedding style by far in the Coconino is small- to large-scale (up to 20 m thick) planar-tabular and planar-wedge cross-stratification (Middleton et al. 2003). It is unusual to find other bedding styles in the Coconino, but when they occur they have been found to be associated with some special features. Whitmore and Strom (2010) reported massive beds (up to 1.0 m thick) at several locations just above sand injectites at the base of the Coconino (Fig. 30). Planar beds have been found in several locations. Some, in Sedona, are associated with parabolic recumbent folds (Whitmore et al. 2015) and others contain dolomite (Andrus Point) or calcite (Kaibab-Buckskin Gulch) as documented by Whitmore et al. (2014). E. Parting lineation features Relief on most flat Coconino foreset surfaces closely resembles “current lineation” or “parting lineation” (Fig. 31). The lineated pattern is always parallel with dip. F. “Raindrop” prints Small pits or crater-like features are rarely found at various Coconino localities (Fig. 25) and have been called “raindrop” prints by some (Hill et al. 2016). In Ash Fork and Seligman, Arizona the features often occur in rows and are parallel to dip instead of being randomly distributed on the rock surface as in some other areas. Sometimes the “pit” extends a centimeter or more through the rock and similar deformation patterns can be found on both sides of thin cm-thick beds (Fig. 32). Small pea-sized nodules (possibly siderite) can fall out of the rock surface to create some pits (Fig. 33). Other features that appear to be raindrop prints when initially observed may be entry/exit points of some small organism that burrowed horizontally in the sediment (Fig. 34); the lateral burrows are not always seen below the surface as in Fig. 34B. The “pits” and “crater-like” features have little resemblance to raindrop prints commonly found in sand (Fig. 35). G. Ripples Features that resemble ripples should not be considered common in the Coconino, but occasionally they can be found and are always parallel to dip (Fig. 36). Sometimes they are found associated with the “raindrop” prints mentioned above. They are often difficult to see because they are commonly very low relief features. Sometimes they are not noticed unless the sun is shining at a low angle on the rock face. H. “Mud cracks” Some have called polygonal cracks within the Coconino “mud cracks” (Hill et al. 2016, p. 68). The cracks (Fig. 37) are polygonal but they only superficially resemble modern mud cracks. They have only been found on bounding surfaces and their origin is still enigmatic (Brand 2018 personal communication; Peters and Brand 1999). The cracks penetrate both downward and upward about 15 cm from bounding surfaces. Laminations continue horizontally through the “cracks” demonstrating that they were never open as true desiccation cracks. I. Sand injectites Large sand-filled cracks, some >15mdeep, occur at some locations at the base of the Coconino Sandstone and penetrate into the underlying Hermit Formation (Fig. 38). The sediment within them is usually massive in nature with some cracks exhibiting vertical “layers” but not Whitmore and Garner ◀ The Coconino Sandstone ▶ 2018 ICC 586 Figure 6. Grain size variation within the Coconino Sandstone (from Whitmore et al. 2014).